Which of the following could be used to calibrate a pressure gage 0 to 800 PSI?

Using a dead weight tester to calibrate a pressure gauge from 0 to 800 PSI is appropriate because it provides a primary standard for pressure measurement. A dead weight tester works by applying known weights to generate a specific pressure, which can be precisely controlled and measured. This method is highly accurate and is commonly used in calibration laboratories and industries for ensuring that pressure instruments, like gauges, are providing correct readings.

The calibration process involves placing the pressure gauge on the dead weight tester and adjusting it to ensure it reads accurately at various set pressures throughout the range. Since dead weight testers are considered a standard for pressure measurement, they can effectively verify the accuracy of a pressure gauge against known values.

In contrast, other options are less suitable for calibration. A mercury manometer, while accurate for low-pressure measurements, may not be practical or safe for higher pressures like 800 PSI and has limitations in terms of portability and calibration ranges. The plant instrument air supply can vary in pressure and may not provide the consistencies needed for precise calibration of a pressure gauge. Lastly, a multi-meter is designed for electrical measurements and would not be applicable for calibrating pressure gauges, as it doesn’t measure pressure directly.